WAL-MART SUPERCENTER PROTOTYPE TESTS ENERGY CONSERVATION

Julie Gallagher

MCKINNEY, Texas -- In an experiment meant to test the limits of energy conservation in retail stores, Wal-Mart Stores opened its first environmentally focused supercenter here last week, projected to be 30% to 50% more energy-efficient than traditional Wal-Mart supercenters.

"This store will contain many of the best resource conservation and sustainable design technologies currently available to minimize the use of energy and natural resources," said Mike Duke, executive vice president, Wal-Mart, and president and chief executive officer of the company's U.S. division, in a statement.

Technology vendors interviewed by SN noted that few if any stores combined as much energy-related technology in one location.

Among the environmental features of the McKinney supercenter are: two energy-producing wind turbines, roof-mounted solar panels, natural light sensors, heat-reducing reflective ceramic paint, radiant floor heating, a rainwater harvesting and treatment system, and a windmill.

The opening comes at a time when Wal-Mart, Bentonville, Ark., is making a concerted effort to improve its public image in the face of critical union activists and community groups. "We are excited that we can lead the way in promoting the use of sustainable building and business practices in retail and the real-estate development process," Duke said.

Information relating to the store's energy-efficiency will be collected, monitored and compared to that of a traditional Wal-Mart Supercenter, also located in McKinney. Testing will be monitored remotely by third-party consultant Oak Ridge National Labs, Oak Ridge, Tenn., over a three-year period. "This is an experimental store, so results will determine what can be improved upon and how we will move forward," said Jim McClendon, mechanical engineering manager, Wal-Mart.

Duke added that Wal-Mart will share its findings from this store -- and a similar store to open this fall in Aurora, Colo., a colder climate -- with the retail industry, the general public and government agencies, and apply them to future Wal-Mart facilities. Plans for the construction of additional experimental stores have not been made.

Many of the experimental store's features work in conjunction with natural resources. For instance, "on a bright day the whole store can be lit by solar power," McClendon said. Its lighting system features sensors that monitor the amount of sunlight entering the store through skylights. These sensors automatically adjust the brightness of fluorescent lamps based on the availability of natural light.

Solar panels have also been installed in areas of the store's roof, including the Garden Center's canopy. Panels in the canopy are estimated to generate 14,585 kilowatt hours of electricity annually, enough to power 486 single-family homes for one day, according to Wal-Mart.

Some of the store's energy needs will be supplemented by a 50-kilowatt wind turbine outside of the store. The energy it produces will reduce electricity consumption by approximately 5%, enough to power 10 average-size homes, Wal-Mart said.

Flashing traffic signs in the store's parking lot are powered 24 hours a day by solar energy collected by panels attached to the signs. The lights on Wal-Mart's outside banner are powered by a second, dedicated wind turbine.

The facility also features a rainwater harvesting and treatment system that captures water from the roof and a portion of the parking lot for irrigating plants and trees used to shade the parking lot. The system also features a windmill used to circulate water purified by plant material.

In addition to water conservation, the new supercenter recycles materials commonly considered waste. For example, tires have been recycled and used to make some of the facility's sidewalks. Motor oil from the store's Tire and Lube Express and used cooking oil from the deli are collected and saved for use in a bio-fuel boiler that generates heat on site to heat the building. The natural gas saves more than 30,000 therms, estimated to be enough to heat and provide hot water for 26 single-family homes in McKinney for a year, Wal-Mart said.

Waste heat drawn from the store's refrigeration system is captured and redirected to heat the radiant floor heating system and the water used in the restrooms' sinks. The radiant floor heating system works to moderate temperatures in colder areas of the store such as the frozen food section and the areas near the store's entrances in the winter.

Wal-Mart's main objective with its experimental stores is education. A Web site, www.walmartfacts.com, features a link to a Web page that provides visitors with comprehensive information on the store's features and its energy consumption. Running consumption totals are updated in real time, and the same information is presented to visitors to the experimental McKinney store on two screens.

The store also features 26 floor signs, each providing customers with information about a specific experiment in the store.